The invention relates to the localized production of purified methane at a waste gas source. As a result of chemical reactions and microbes acting upon waste, landfills and anaerobic digesters produce usable quantities of flammable, biogenic gas, known as landfill gas (LFG) or biogas, respectively. While these gas products contain a high percentage of methane, the primary constituent of compressed natural gas (CNG), LFG and biogas in their raw form have limited uses as a fuel. Biogas and LFG contain varying amounts of nitrogen, carbon-dioxide, oxygen, water vapor, hydrogen-sulfide, and other contaminants. Most of these other contaminants are known as “volatile organic compounds” or VOCs. The VOCs usually make up less than one percent of LFG or biogas.
A group of VOC's know as siloxanes can also contaminate the biogas and LFG making it unsuitable for use as a fuel. Siloxane compounds are frequently found in municipal solid waste and municipal wastewater. In landfills and digestion facilities accepting these materials as a component of the feedstock, siloxanes volatilize into biogas. When this gas is combusted in a gas engine, turbine or boiler, siloxanes are converted into silicon dioxide (SiO2) which deposits internally in the combustion chamber, increasing wear and tear.